Premature optimization, noted Donald Knuth, is the root of all evil. Mediocrity, you might say, is resistance to optimization under conditions where optimization is always premature. And what might such conditions be?
Infinite game conditions of course, where the goal is to continue the game indefinitely, in indeterminate future conditions, rather than win by the rules of the prevailing finite game. Evolution is the prototypical instance of an infinite game….
Mediocrity is not a position on some sort of performance spectrum, but a metacognitive attitude towards all performance that leads to middling performance on any specific performance spectrum as a side effect.